This mega-patch rips out the FixNesting implementation and the related
ChildDef components. The primary algorithmic change is to convert from
use of tokens to tree nodes, which are far more amenable to the style
of processing that FixNesting uses. Additionally, FixNesting has been
changed to go bottom-up rather than top-down, in order to avoid needing
to implement backtracking.
This patch simplifies a good deal of the relevant logic, since we no
longer need to continually recalculate the nesting structure when
processing things. However, the conversion to the alternate format
incurs some overhead, so for small inputs these changes are not a win.
One possibility to greatly reduce the constant factors here is to switch
to entirely using libxml's representation, and never serializing tokens;
this would require one to rewrite injectors, however.
The iterative post-order traversal in FixNesting is a bit subtle, but
we have essentially reified the stack and continuations.
We've removed support for %Core.EscapeInvalidChildren.
Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
The purpose of this addition is twofold. In trusted mode, iframes are
now unconditionally allowed.
However, many online video providers (YouTube, Vimeo) and other web
applications (Google Maps, Google Calendar, etc) provide embed code in
iframe format, which is useful functionality in untrusted mode.
You can specify iframes as trusted elements with %HTML.SafeIframe;
however, you need to additionally specify a whitelist mechanism such as
%URI.SafeIframeRegexp to say what iframe embeds are OK (by default
everything is rejected).
Note: As iframes are invalid in strict doctypes, you will not be able to
use them there.
We also added an always_load parameter to URIFilters in order to support
the strange nature of the SafeIframe URIFilter (it always needs to be
loaded, due to the inability of accessing the %HTML.SafeIframe directive
to see if it's needed!) We expect this URIFilter can expand in the future
to offer more complex validation mechanisms.
Signed-off-by: Bradley M. Froehle <brad.froehle@gmail.com>
Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
When viewing potentially hostile html, it may be helpful to see what
a given link was pointing to. This new injector takes the href
attribute and adds the text after the link, and deletes the href
attribute.
Other forms of display could easily be contrived, but this seems to be
a good basic way to present the information.
Signed-off-by: David Morton <mortonda@dgrmm.net>
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
Also changed:
- DirectLex keeps track of column numbers in context
- New class HTMLPurifier_ErrorStruct
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
* Added Charsets and Character attribute types
* Fix a heavily recursive form of ContentSets, this allows a content-set
to include another content-set which includes another content-set, and
so forth.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
By default, the DirectLex and DOMLex behavior with stray angled brackets
varied a great deal due to their implementations. A little known directive
%Core.AggressivelyFixLt attempted to match DOMLex's behavior with DirectLex's,
but it was off by default. By turning it on by default, users now enjoy these
benefits, and performance-minded users can turn it back off.
Also, several refinements to stray angled bracket parsing was made. Specifically:
* DirectLex: Handle each left angled bracket individually, which prevents
strange behavior as reported by eon.
* DOMLex: Iterate aggressive lt fix, so that stacked brackets like << are
handled.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
